The human thighbone has an interesting past—it has been used as a natural club or other tool, and in some cultures it has been used as a musical instrument in sacred ceremonies.
As the only bone found in the thigh, the femur is not only the longest, but also the strongest bone in the human skeleton. A healthy human femur can resist forces of up to 2,500 pounds. Consequently, it takes a significant amount of force or weight, such as a substantial fall or a motor vehicle crash, to fracture a femur.*
Another notable fact about the femur is the role it plays in determining an individual’s vertical height. Feldesman and colleagues sampled the femur/stature ratio on 51 different populations around the world and found that the femur is responsible for, on average, more than a quarter of a person’s height.†
The spectrum of femur fractures varies widely from non-displaced stress fractures to those associated with severe comminution and major soft tissue injury. Fractures are described by location (proximal, shaft, distal), as well as by mechanism of injury. The three major mechanisms of injury are high-energy traumatic fractures, low-energy pathologic fractures, and stress fractures as a result of repetitive motion. The femur is a highly vascularized bone, and when it is fractured it may result in significant bleeding into the thigh. As many as 40 percent of isolated fractures may require a transfusion, as these injuries can account for up to three units of blood.‡
To examine the occurrence of femur fractures contained in the National Trauma Data Bank® (NTDB®) research dataset admission year 2015, medical records were searched using the International Classification of Diseases, Ninth Revision, Clinical Modification codes. Specifically searched were records that included a diagnosis code of 820 (fracture of neck of femur) or 821 (fracture of other and unspecified parts of femur). A total of 105,460 records were found, of which 97,117 contained a discharge status, including 33,888 patients discharged to home, 21,495 to acute care/rehab, and 38,836 to skilled nursing facilities; 2,898 died. Women accounted for 55 percent of these patients who, on average, were 62.8 years of age, had an average hospital length of stay of 6.9 days, an intensive care unit length of stay of 6.3 days, an average injury severity score of 11.7, and were on the ventilator for an average of 6.6 days. Of those tested for alcohol, more than 28 percent (6,373 out of 22,376) tested positive. Only a minority of patients (approximately one-third) were discharged to home. (See Figure 1.)
Figure 1. Hospital discharge status
Make no bones about it, the femur is a special bone, both for its place in history and for the role it plays in determining an individual’s skeletal height and its weight-bearing capacity. Whether you suffer a traumatic fracture, pathologic fracture, or stress fracture, it will be a while before you are able to get back up on your feet and walk again.
Throughout the year, we will be highlighting these data through brief monthly reports in the Bulletin. The NTDB Annual Report 2016 is available on the American College of Surgeons’ website as a PDF file. In addition, information is available on our website about how to obtain NTDB data for more detailed study. If you are interested in submitting your trauma center’s data contact Melanie L. Neal, Manager, NTDB at firstname.lastname@example.org.
*Healthline Media. Femur. Available at: www.healthline.com/human-body-maps/femur. Accessed March 6, 2017.
†Feldesman MR, Kleckner JG, Lundy JK. Femur/stature ratio and estimates of stature in mid- and late-Pleistocene fossil hominids. Am J Phys Anthropol.1990;83(3):359–372.
‡Romeo NM, Deitch JR, DePasquale TG. Femur injuries and fractures. Medscape. October 2015. Available at: emedicine.medscape.com/article/90779-overview. Accessed March 6, 2017.